To turn off the friendly error message option in the web browser:
- In Internet Explorer:
- On the Tools menu, click Internet Options.
- On the Advanced tab, under the Browsing section, click to clear the Show friendly HTTP error messages check box, and then click OK.
- Close the browser.
- For Mozilla Firefox:
- Open up a new tab (CTRL+T) or window (CTRL+N).
- Type in the addressbar: about:config.
- In the filterbar type: error and press Enter.
- Now set the value of the browser.xul.error_pages.enabled to true. Double clicking will do.
- Restart Firefox.
Any web developer should have this feature turned off by default.
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